Undefined behavior in C is a reading error

Re:Undefined behavior in C is a reading error by im3w1l on Friday May 21, 2021 @05:02AM (#27231866)

What I never see mentioned in this type of discussion is what this compiler trick buys us. Like how much faster does my program run because of deductions like these? And are there any patterns that particularly benefit from it? Could they hint the constraint manually?

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Re:Undefined behavior in C is a reading error by mpcjanssen on Friday May 21, 2021 @06:07AM (#27232213)

There are plenty of examples in this thread alone.

In my opinion hinting won't help. Everyone who cares about the performance gain will enable the hint (which I expect will be almost everyone) so you have won nothing but added noise with the hint.

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Re:Undefined behavior in C is a reading error by vyodaiken on Friday May 21, 2021 @08:53AM (#27233387)

There is not a single compelling example. Just contrived examples with dubious speedups and obvious errors.

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